When she was “too tired to teach,” Jill Borriello showed her sixth-grade class at JHS 78 in Brooklyn a violent movie: “Sleeping with the Enemy.”

When her students were “bored,” she let them pick up her cellphone to play video games. One boy read a lewd message from Borriello’s boyfriend and saw racy photos of the teacher in lingerie, according to a report by Special Schools Investigator Richard Condon.

Students at the Flatlands middle school told investigators that Borriello showed the R-rated flick starring Julia Roberts as a battered wife last February because “she did not sleep well the night before” and “did not feel like teaching that day.”

The film is so brutal and scary that critic Roger Ebert called it a “slasher movie in disguise.”Borriello, who made $59,156 in 2011, explained she “wanted to illustrate the proliferation of violence against women by men,” because singer Rihanna was in the news after a beating by boyfriend Chris Brown.

The student who picked up Borriello’s cellphone said she left it open and sometimes let him take it off her desk. He read a sexy message sent to Borriello: “I can’t wait to see you so I can lick you from head to toe.” He also saw four photos of Borriello on a bed in black lingerie, the report says.

A city Department of Education spokeswoman said Borriello received an “unsatisfactory rating and appropriate discipline,” but would not elaborate.